The complex entity which shows geometrical as well as optical isomerism, is :

Options

A. `[Co(gly)_(3)]`
B. `[Co(gly)(NH_(3))_(4)]^(2+)`
C. `[CoCl_(2)(NH_(3))_(4)]`
D. All of these

Explanation

To determine the complex entity that shows both geometrical and optical isomerism, we will analyze the options provided in the question step by step.

### Step 1: Understand Geometrical Isomerism
Geometrical isomerism occurs when ligands occupy different positions around a central metal atom, leading to different spatial arrangements. The two common forms of geometrical isomerism are:
- **Cis Isomer**: Ligands are adjacent to each other.
- **Trans Isomer**: Ligands are opposite each other.

### Step 2: Understand Optical Isomerism
Optical isomerism occurs when a molecule cannot be superimposed on its mirror image, indicating the absence of a plane of symmetry. Such compounds are chiral and can rotate plane-polarized light.

### Step 3: Analyze the Ligands
In the question, we need to identify a complex that can exhibit both types of isomerism. We will consider the ligands and their arrangements around the central metal atom.

### Step 4: Evaluate the Given Complexes
1. **Cobalt-Glycine Complex**: Glycine is a bidentate ligand, which can form facial and meridional isomers. This complex can show both geometrical (facial and meridional) and optical isomerism due to the absence of a plane of symmetry.

2. **Cobalt with Cl2 and NH3**: This complex can show geometrical isomerism (cis and trans forms) but will have a plane of symmetry, thus it cannot exhibit optical isomerism.

3. **Cobalt with other ligands**: Similar analysis can be applied to other complexes, but they either show only geometrical isomerism or have a plane of symmetry, preventing optical isomerism.

### Step 5: Conclusion
Based on the analysis, the complex entity that shows both geometrical and optical isomerism is the **Cobalt-Glycine Complex**.

### Final Answer
The complex entity which shows geometrical as well as optical isomerism is: **Cobalt-Glycine Complex**.

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